1 /*
2  *	This simple classical example of recursion is useful for
3  *	testing stack backtraces and such.
4  */
5 
6 #ifdef vxworks
7 
8 #  include <stdio.h>
9 
10 /* VxWorks does not supply atoi.  */
11 static int
12 atoi (z)
13      char *z;
14 {
15   int i = 0;
16 
17   while (*z >= '0' && *z <= '9')
18     i = i * 10 + (*z++ - '0');
19   return i;
20 }
21 
22 /* I don't know of any way to pass an array to VxWorks.  This function
23    can be called directly from gdb.  */
24 
25 vxmain (arg)
26 char *arg;
27 {
28   char *argv[2];
29 
30   argv[0] = "";
31   argv[1] = arg;
32   main (2, argv, (char **) 0);
33 }
34 
35 #else /* ! vxworks */
36 #  include <stdio.h>
37 #  include <stdlib.h>
38 #endif /* ! vxworks */
39 
40 #ifdef PROTOTYPES
41 int factorial (int);
42 
43 int
44 main (int argc, char **argv, char **envp)
45 #else
46 int
47 main (argc, argv, envp)
48 int argc;
49 char *argv[], **envp;
50 #endif
51 {
52 #ifdef usestubs
53     set_debug_traps();
54     breakpoint();
55 #endif
56 #ifdef FAKEARGV
57     printf ("%d\n", factorial (1));
58 #else
59     if (argc != 2) {
60 	printf ("usage:  factorial <number>\n");
61 	return 1;
62     } else {
63 	printf ("%d\n", factorial (atoi (argv[1])));
64     }
65 #endif
66     return 0;
67 }
68 
69 #ifdef PROTOTYPES
70 int factorial (int value)
71 #else
72 int factorial (value) int value;
73 #endif
74 {
75     int  local_var;
76 
77     if (value > 1) {
78 	value *= factorial (value - 1);
79     }
80     local_var = value;
81     return (value);
82 }
83